This 6" x 6" x 3/8" Galvanized Plate is designed for such a purpose

Install a bar at every corner

This hinge has a 5/8” diameter pin with a ball bearing and grease fitting for lubrication

and the arm's galvanized steel build provides superior rust resistance

and (1) 4" Classic Cap Assy (Sold as Vinyl Railing Post Kit)

LiftMaster Std. Duty Roller Cage Bearing Hinge - Bolt to Gate, Bolt to Post (Prime Coated) Sold in pairs. Hinge This 6" x 6" xLiftMaster Std. Duty Roller Cage Bearing Hinge Bolt to Gate, Bolt to Post (Prime Coated) Heavy Duty Construction for Maximum Durability Dependable Roller Cage Bearing Design Even Weight Distribution Five Times The Weight Bearing Surface of the Nearest Large Hinge Convenient Bolt On Model Easy to Fully Lubricate Specifications: Maximum Gate Weight: Up to 1,000 lbs. per pair. Sold in pairs. Pair (2 per Box) 7. 1 lbs. 3. 2 kgs.